Abstract: A high acceleration time shift control apparatus and method for a vehicle is provided. The high acceleration time shift control apparatus includes a transmission which achieves plural shift speeds whose gear ratios are different from each other; and a high acceleration time upshifting control device which changes a shift speed of the transmission to a higher speed based on a predetermined determination rotational speed such that an input rotational speed of the transmission substantially reaches a target maximum rotational speed when a request for high acceleration is made by a driver.

Abstract: A back up alarm system for a vehicle including a sensor for generating a vehicle motion status signal with a vehicle reverse gear engaged. The vehicle motion status signal includes a base electrical signal when the vehicle is stationary and the vehicle motion status signal includes a threshold electrical signal when the vehicle is moving in a reverse direction. A controller is operatively connected to the sensor and receives the vehicle motion status signal from the sensor. The controller activates a first alarm in response to the base electrical signal including at least one of an audible warning signal and a visual warning signal. In response to the threshold electrical signal, the controller activates a second alarm including at least one of an audible warning signal and a visual warning signal.

Abstract: A gearshift to transmission controller interface is based on a controller area network and a gearshift interface interposed between the gearshift and associated displays and the network bus. The shift controller can be made universal to all transmission types of automated manual transmissions by incorporation of a library program relating to a transmission type.

Abstract: A shift control ECU includes the steps of storing a position of a shift lever; starting a count-up timer when the shift lever comes to a neutral position; and recognizing a driver's request for the neutral position when a count-up timer value attains TN(1) if the stored shift lever position is a home position and when a count-up timer value attains TN(2) if the stored shift lever position is not the home position. Here, TN(1) is set to be smaller than TN(2).

Abstract: An electronic control system includes two speed sensors connected to a microcontroller that is configured to read the sensors and perform the process of determining the gear ratio of a vehicle gearbox. The process includes calculating (several times) which of at least two gear ratios the gearbox is engaged in, then adding up the number of times each of the gear ratios was calculated, and then selecting the gear ratio that was calculated the most times as the true gear ratio.

Abstract: A method for controlling the shifting operation of an automated twin-clutch transmission includes executing a shifting operation between a load gear and a target gear assigned to a first transmission unit by using an intermediate gear assigned to a second transmission unit. The engine speed is adjusted to reach the synchronous speed of the target gear at the end of the shifting operation. At the start of the shifting operation an initial target speed gradient is set such that the engine speed reaches the synchronous speed at the end of the shifting operation based on an estimated total shifting time. The actual shifting progress is determined during the shifting operation and is compared with the estimated shifting progress. The target speed gradient is adjusted to the actual shifting progress in case the actual shifting progress and the estimated shifting progress deviate from one another.

Abstract: A performance enhancement system incorporating a controller, an engine tachometer and a visual indicator light which illuminates within a predetermined range of engine RPMs and which may be separately mounted as required in the driver's visual focal plane to reduce visual distractions, aiding the driver in optimizing torque transference to the tires of a drag racing vehicle.

Abstract: Methods, systems and circuits for analyzing the performance of a vehicle having an electrical system are provided which determine a shift point while the vehicle is being driven. The shift point is determined using acceleration data and RPM data generated from the electrical system.

Abstract: An evaluation system for vehicle operating conditions which is applied to a vehicle provided with an engine (1) and a manual transmission (8) connected to the engine (1) comprises a sensor (21, 24) for detecting the operating conditions of the engine (1) and a controller (30). On the basis of the operating conditions of the engine (1), the controller (30) determines whether or not the fuel economy of the vehicle would be improved by shifting the transmission (8) upward from the current gear position to a gear position one step further toward a HIGH side, and instructs a driver to shift the transmission (8) upward when it is determined that the fuel economy of the vehicle would be improved by shifting the transmission (8) upward.

Abstract: A driving force control apparatus for a vehicle includes an accelerator opening sensor that detects an accelerator opening for a vehicle, and an automatic transmission control device that controls an automatic transmission based on road information and the accelerator opening. The automatic transmission control device, in an interval prior to a deceleration required interval, controls an automatic transmission so as to ease a shifting operation that corresponds to a decrease in the accelerator opening.

Abstract: Specific shift positions of an electrically actuated vehicle transmission, such as first to fifth, neutral and reverse gears, are detected by monitoring one or more characteristic electrical variables, e.g., actuator currents, during a shift movement of the transmission and by correlating increased or decreased levels of current with the arrival at or passage through the specific shift positions.

Abstract: A pressure control for the program-controlled drive of at least one pressure actuating member influences the hydraulic constellation in a transmission via the pressure (p). The program-controlled drive takes place via changes of states (z; Z0, Z1, Z2, Z3, Z4, Z5, Z6, Z7) from current states (z(t)) to subsequent states (z(t+1)) and that the states (z; Z0, Z1, Z2, Z3, Z4, Z5, Z6, Z7) are all configurable without change of program. A method is provided for the program-controlled drive of at least one pressure actuating member.

Abstract: In a vehicle in which a moderate throttle opening degree control of maintaining a degree of throttle opening that is less than a degree of throttle opening that corresponds to an accelerator operation is performed for a predetermined period following a beginning of the accelerator operation, if it is determined that a clutch-to-clutch downshift judgment has been made, the reduction of the engaging pressure of a disengage-side friction engagement device is restrained until it is determined that the moderate throttle opening degree control has ended. Therefore, even if the turbine torque is returned to a normal value at the end of the moderate throttle opening degree control, insufficient engaging torque is avoided, and the takeover of engaging torque for the clutch-to-clutch downshift is smoothly performed while the turbine torque is stable. Hence, occurrence of a shock related to the end of the moderate throttle opening degree control is suitably prevented.

Abstract: A shift control ECU includes the steps of storing a position of a shift lever; starting a count-up timer when the shift lever comes to a neutral position; and recognizing a driver's request for the neutral position when a count-up timer value attains TN(1) if the stored shift lever position is a home position and when a count-up timer value attains TN(2) if the stored shift lever position is not the home position. Here, TN(1) is set to be smaller than TN(2).

Abstract: A shift control system rotates an actuator to allow a wall of a detent plate and a roller of a detent spring to contact each other and then detects the position of contact so as to detect the position of the wall of the detent plate. After the wall position is determined, the actuator is driven in the direction opposite to the wall until the actuator reaches a position located before the wall position and distant therefrom by a predetermined amount, in order to cancel flexure or extension of the detent spring that is caused when the detent spring is pushed against the wall of the detent plate. Accordingly, such a situation where the shift position is moved by the recovery force of the detent spring can be avoided.

Abstract: A shift control system for a V-belt type continuously variable transmission is provided. The shift control system comprises a controller programmed to store an actual transmission ratio of the continuously variable transmission at stop of an associated vehicle drive source, and inhibit, at restart of the vehicle drive source, an initializing operation for returning an operational position of the shift actuator to a standard position when the actual transmission ratio is more on a high-speed side than a predetermined transmission ratio. A shift control method is also provided.

Abstract: An engine control system controls engine torque to transition through the transmission lash zone. The transmission lash zone is determined using speed ratio across the torque converter. When near the transmission lash zone, engine torque is adjusted at a predetermined rate until the system passes through the transmission lash zone. By limiting the change of torque in this way, driveability is improved and it is possible to quickly and reliably provide negative engine torque for braking.

Abstract: A performance enhancement system incorporating a controller, an engine tachometer and a visual indicator light which illuminates within a predetermined range of engine RPMs and which may be separately mounted as required in the driver's visual focal plane to reduce visual distractions, aiding the driver in optimizing torque transference to the tires of a drag racing vehicle.

Abstract: A shift control method and system is disclosed in which the number of shift signals generated within a predetermined time period after a first shift signal is determined and compared to a predetermined number. If the number is equal to or greater than the predetermined number then the shift according to a prior signal must be completed before the next shift is performed. The system includes a control unit and sensors for controlling the transmission according to the disclosed method. The system and method thus prevents or reduces shift shock by ensuring that hydraulic control is properly routed within the transmission.

Abstract: An automatic transmission is driven by an engine through a torque converter. The transmission includes a plurality of friction elements which are selectively engaged to provide a selected gear thereby to transmit the power of engine to an output shaft of the transmission while changing the rotation speed. A speed change completion degree estimating system is provided, which comprises a first section that derives a difference (Nt−Ne) between an input rotation speed (Nt) of the transmission and an engine rotation speed (Ne); a second section that derives a difference (g×No−Ne) between the input rotation speed (g×No) of the transmission provided after completion of the speed change operation and the engine rotation speed (Ne); and a third section that calculates a speed change completion degree (Shift) of the transmission by using a ratio between the (Nt−Ne) and the (g×No−Ne).

Abstract: A fault diagnosis method is provided in which it is possible to determine whether the input shaft speed sensor of the automatic transmission is faulty by using the signals of the output shaft speed sensor, the brake switch, the engine speed sensor and so on, without making use of the signal of the vehicle speed sensor. Moreover, even if there are faults in the output shaft speed sensor or if the shift lever is positioned in the parking P range or the neutral N range, or if the engine speed is lower than the stall speed, the fault diagnosis method for the input shaft speed sensor can be performed, and additionally, a possibility of a misjudgment caused by a bad N-D hydraulic pressure response at an extremely low temperature can be removed.

Abstract: A transmission control system for controlling a transmission is provided with a shift lever whose position is changeable through a lever-shifting action by a driver selecting a transmission stage to be changed into, a transmission stage detection unit for detecting a new position of the shift lever due to the lever-shifting action, and outputting corresponding signals, and a transmission control unit receiving the signals from the transmission stage detection unit and performing a gear-shifting operation of the transmission, the transmission control unit having therein a time map being of a number of values of permissible time intervals that respectively correspond to all kinds of gear-shifting operations of the transmission, the transmission control unit allowing the currently performed gear-shifting operation to be held only during a corresponding permissible time interval set in the time map in a case that it receives another transmission shift request while the gear-shifting operation is currently being p

Abstract: A decision is made as to whether a vehicle is traveling in an uphill traveling mode or in a downhill traveling mode with reference to an incremental running resistance &Dgr;R determined on the basis of a running resistance that will act on the vehicle while the vehicle is traveling in a flat road traveling mode. A desired traction Fd for a full-open throttle state in which a throttle valve is fully open is set if the vehicle is in the uphill traveling mode by using the incremental running resistance &Dgr;R, and a desired traction Fd for a full-closed throttle state in which the throttle valve is fully closed is set if the vehicle is in the downhill traveling mode by using the incremental running resistance &Dgr;R. The desired traction Fd and an achieved traction F(t) in the full-open throttle state at a present traveling speed V are compared if the vehicle is in the uphill traveling mode.

Abstract: A system for controlling an automated mechanical change-gear transmission system including a processing unit for processing inputs according to predetermined logic rules to determine currently engaged and allowably engaged gear ratios and throttle positions, for changing between automatic and semi-automatic transmission modes, for issuing command output signals to non-manually controlled operators, and for temporarily selectively overriding a pre-selected transmission mode if either cruise control or power take off are activated.

Abstract: A method is proposed for controlling an automatic transmission driven by a prime mover in which a shift from a first transmission ratio to a second transmission ratio occurs in the form of a pull upshift or push downshift or a pull downshift or push upshift by a first clutch opening and a second clutch closing and an electronic transmission control device controls, via electromagnetic valves, the pressure curve of the first and of the second clutch during the shifting operation. The shifting operation is divided into various shifting phases, an engine intervention taking place in the load-transfer (LÜ) of the gradient-setting phase (GE), the sliding phase (GL), the gradient-reduction phase (GA) and the closing phase (S), an engine torque and/or a characteristic value that determines the engine torque being transferred from the transmission control device to an engine control device of the prime mover.

Abstract: A method of shortening response time during a gear shifting operation process is applicable to a semi-automatic, electronically controlled transmission of motor vehicles, in particular utility vehicles, takes into account a driver's reaction time to reduce delay in clutch re-engagement. To initiate a gear-shifting operation in such a transmission, the driver actuates a shifting command emitter and at the same time disengages a clutch typically by depressing a clutch pedal. In response thereto, a newly selected gear is engaged in the transmission by an electronic system using outside force assistance, for example compressed fluid. The driver is informed via an acknowledgment device when the clutch can be properly engaged once more.

Abstract: A controller 10 calculates a target drive force based on an accelerator pedal operation amount and a vehicle speed. A speed ratio for calculating a target engine torque is calculated based on the state of the transmission 2. The target engine torque is calculated by dividing the target drive force with the speed ratio for calculating the target engine torque. The torque of the engine 1 is controlled so that the torque of the engine 1 coincides with the target engine torque. During reverse vehicle operation, the speed ratio for calculating target engine torque is corrected to a larger value. In this manner, it is possible to suppress the drive force during reverse vehicle operation while using almost all processes for calculating the target drive force in common during forward and reverse vehicle operation.

Abstract: An automatic transmission controller having automatic-shifting-to-neutral control is provided, wherein automatic-shifting-to-neutral control is notified to a driver so as not give him a sense of incongruity and it is prohibited on a slope so as to prevent backward moving of a vehicle. In an automatic transmission controller having automatic-shifting-to-neutral control for shifting the automatic transmission to neutral when a vehicle is continuously stopped in an idling state for a predetermined time, the automatic transmission controller comprises automatic-shifting-to-neutral notifying/warning means for notifying the automatic-shifting-to-neutral state, slope detecting means for detecting that the vehicle is on a slope, and automatic-shifting-to-neutral control prohibiting means for prohibiting the automatic-shifting-to-neutral control when it is detected that the vehicle is on the slope.

Abstract: A method for determining a shift stage (transmission ratio) for a discretely shifting transmission of a motor vehicle wherein an output rpm of the transmission is detected and an optimal motor rpm is pregiven. It is provided that computed and/or measured input rpms (22, 23) of the transmission are detected. An rpm (25, 26) for each shift stage is fixed via a hysteresis circuit (24), a difference of the input rpm (22) of a next-higher shift stage and the rpm (26) supplies an upshift limit (10) and a sum of current input rpm (23) and the rpm (25) supplies a downshift limit (12); and, shifting into a higher shift stage takes place when the upshift limit (10) exceeds the optimal motor rpm (28) or shifting into a lower shift stage takes place when the optimal motor rpm (28) exceeds the downshift limit (12) (shifting necessity (27)).

Abstract: Disclosed is a shift control method comprising the steps of determining if an input shift signal is a power-on upshift signal; determining if driving conditions satisfy power-on upshift learn conditions if the input shift signal is a power-on upshift signal; performing power-on upshift control if power-on upshift learn conditions are satisfied; learning an initial fill time and completing shifting; determining if shifting is completed; determining if run-up occurred during the shift operation if shifting is completed; determining if interlocking occurred if run-up did not occur; determining, if interlocking occurred, if the interlocking is above a predetermined level; and learning a fill time if the interlocking is above the predetermined level.

Abstract: An apparatus for determining a failure of wheel speed sensors, which is capable of properly determining whether or not a wheel speed detection system including the wheel speed sensors has failed, if at least a wheel speed detected by the wheel speed sensors indicates a stopped state of a corresponding wheel. An engine rotational speed is detected, and an input-output rotational speed ratio of a torque converter of an automatic transmission mounted in the vehicle is calculated. A shift range of the automatic transmission is detected. Whether or not the vehicle is traveling is determined based on the engine rotational speed and the input-output rotational speed ratio when the automatic transmission is in a traveling range. It is determined that the wheel speed detection system including the wheel speed sensors has failed, if it is determined that the vehicle is traveling, and at the same time, at least one of wheel speed sensors indicates a stopped state of a corresponding one of the wheels.

Abstract: The driving force control system calculates a target driving force Tt* and then calculates a target engine torque Te* from a target driving force Tt* and a target calculated engine torque gear ratio. When the transmission is not shifting, the driving force control system uses a gear ratio determined by the gear position as the target calculated engine torque gear ratio. When the transmission is shifting, the driving force control system uses an actual gear ratio calculated from the input and output rotational speeds. This gear ratio switching control makes it possible to vary the target engine torque Te* gradually in response to the change of the actual gear ratio during shifting. Thus, a dip in the output torque is eliminated, and the shifting shock is mitigated to a satisfactory level.

Abstract: Within the scope of the method for motor reduction while closing the lock-up clutch for automatic transmission of a motor vehicle, the starting value of the motor reduction is brought up via an adjustable ramp within the time period elapsed while laying on the disks of the lock-up bridge clutch, the motor reduction being adjustable with reference to a characteristic field.

Abstract: A first switch (2) which can select a manual mode, and a second switch (5, 6) which can select one of an upshift and a downshift, are provided. A microprocessor (1) varies a speed ratio of an automatic transmission (10) according to the specification of the second switch (5, 6) when the first switch (2) has previously selected the manual mode, and the second switch (5, 6) subsequently specifies one of the upshift and the downshift (S20, S21, S33, S40, S41, S34, S36, S37, S53, S54, S55). On the other hand, variation of the speed ratio of the automatic transmission (10) according to the specification of the second switch (5, 6) is prohibited when the second switch (5,6) specifies one of the upshift and the downshift at a timing not later than a timing at which the manual mode is selected by the first switch (2) (S20, S22, S33, S40, S38, S34, S36, S38, S53, S54, S56).

Abstract: A shift control method for an automatic transmission includes the steps of determining if upshift conditions are satisfied; determining if throttle valve opening is below a power on/off check line if upshift conditions are satisfied; determining, if throttle valve opening is below the power on/off check line, whether a change in throttle valve opening in a closed direction is less than a predetermined value; and preventing upshifting if the change in throttle valve opening in the closed direction is less than the predetermined value.

Abstract: A control apparatus is used to control a hybrid vehicle having an internal combustion engine, a stepwise variable transmission capable of automatic speed shifting, a clutch disposed between the internal combustion engine and the stepwise variable transmission for discontinuing and establishing power transfer to and from the stepwise variable transmission, an electric motor, etc. The control apparatus calculates a timing of the stepwise variable transmission starting an automatic shifting operation, and gradually decreases the torque assist based on the motor torque Tm of the electric motor prior to the start of the shifting operation, so as to reduce the stepped change in the drive torque that occurs when the engine torque Te is eliminated upon disengagement of the clutch during the shifting operation. This operation of the control apparatus also gentles or reduces the gradient of torque change. The shock at the time of shifting is thus reduced.

Abstract: The invention proceeds from a system for adjusting a motor vehicle transmission, which is changeable in its transmission gear ratio, the transmission having an efficiency characteristic which is dependent on the transmission gear ratio. A first quantity is detected which represents the actual transmission output rpm and a second quantity is determined which represents a desired value for the drive torque. Then, a desired rpm of the vehicle engine is determined at least in dependence upon the detected first quantity and the determined second quantity and in dependence upon the efficiency characteristic of the transmission. The adjustment of the transmission gear ratio takes place in dependence upon the desired rpm of the vehicle engine which is so determined. With the invention, transmission influences are considered in the determination of the optimal transmission gear ratio within a system for the coordinated drive train control.

Abstract: An electronic control system for a transmission in a work vehicle such as an agricultural tractor is provided herein. The system includes sensors for detecting the output speed of the vehicle engine, the output speed of the transmission and the vehicle ground speed. Command devices are available to the vehicle operator for generating command signals, such as for commanding the direction of movement, as well as forward and reverse gear ratios. A controller receives signals from the sensors and command devices, and controls engagement and disengagement of combinations of fluid clutches in the transmission to obtain desired gear ratios between the transmission input and output shafts. The system stores default forward and reverse gear ratios which are used upon start-up of the vehicle. To permit limited modification of the default gear ratios, an interface separate from the vehicle is provided to modify the default gear ratios.

Abstract: A control apparatus for a vehicle that has a power source and a continuously variable transmission. If a backlash-reducing control execution flag is on, a central control section utilizes an inertia torque produced during a backlash-reducing control as a part of a transient surge-reducing control that follows the backlash-reducing control, by setting at least one of a control duration and a control torque of the transient surge-reducing control to a value that is less than the control duration or torque set for an ordinary transient surge-reducing control. Therefore, the vehicle control apparatus is able to effectively perform the transient surge-reducing control and therefore further reduce vibrations of the vehicle.

Abstract: A method for controlling automatic transmission downshift phases. The method determines conditions in which the downshift passes from normal operating conditions based on predetermined passage laws to special downshift operating conditions, and senses the passage to the special operating conditions. On sensing the passage to the special operating conditions, downshifting is effectuated by passing from the current gear ratio to a lower gear ratio, and blocking the lower gear ratio until the special downshift operating conditions disappear.

Abstract: A control unit for an automatic transmission of a motor vehicle has a position detection sensor that supplies an analog output signal that is dependent on a position of a selector slide. The position detection sensor is adjusted using a self-learning algorithm in an electronic control system of the control unit during operation of the motor vehicle.

Abstract: A lock-up control device is provided to control the engaging and release of a lock-up clutch, which is arranged in parallel with a torque converter to transmit driving force of an engine of a car. Herein, target driving force is calculated based on accelerator pedal opening and car velocity. A present shift position is detected using a shift map based on accelerator pedal opening, car velocity and engine speed. Target engine torque is calculated based on the target driving force and present shift position as well as a torque amplification ratio, which is detected when the torque converter is placed in a torque amplification state. A lock-up release instruction is issued under conditions that the torque converter is placed in the torque amplification state while the target engine torque is greater than a preset value, which is determined in advance based on a torque characteristic of the engine.

Abstract: A transmission includes a transmission input speed sensor which generates transmission input speed signals indicative of an input speed to the transmission and a transmission output speed sensor which generates transmission output speed signals indicative of an output speed of the transmission. The transmission further includes a controller operable to receive the transmission input speed signal and the transmission output speed signal and determine a transmission ratio based on the transmission input speed signal and the transmission output speed signal. The controller is further operable to calculate a rate of change of the transmission ratio and initiate a transmission range shift based on the transmission ratio, the rate, and a shift completion ratio such that the transmission range shift is completed when the transmission is at the predetermined shift completion ratio.

Abstract: A method for determining the onset of positive torque through an automatic transmission (the power-on point), includes saving engine torque magnitudes within a specified tolerance of each other and within a adaptive limits, the highest torque value of the sampled torque magnitudes being stored in memory. The saved value plus a calibrated safety margin is used to compare to the calculated transmission input torque. If the input torque is higher, the powertrain is considered “power-on.” In addition to the safety margin, other calibratable adder torque values can be used to compensate for air conditioning, electrical loads, temperature, etc. If the samples fall below the lower adaptive limit, the lower limit is used plus any torque adders. If the adaptive samples are above the adaptive limit, the upper adaptive limit is used without any torque adders. A calibrated baseline torque value is used for power-on determination until enough valid samples are obtained.

Abstract: An interactive engine and automatic transmission control system is provided wherein spark and air control are used to control engine speed to maintain a small positive torque on the transmission before and after coast down shifts. More particularly, a transmission controller is electrically coupled to an engine controller in a motor vehicle such that information can be passed therebetween. Such information includes a start of shift signal, a phase of the shift signal (i.e., clutch release phase, speed change phase, or clutch application phase), and a shift complete signal. In addition, the transmission controller identifies the type of shift that is occurring (i.e., fourth gear to third, third to second, or second to first), transmission oil temperature and the acceleration (braking) rate of the vehicle to the engine controller.

Abstract: An engine control system controls engine torque to transition through the transmission lash zone. The transmission lash zone is determined using speed ratio across the torque converter. When near the transmission lash zone, engine torque is adjusted at a predetermined rate until the system passes through the transmission lash zone. By limiting the change of torque in this way, driveability is improved and it is possible to quickly and reliably provide negative engine torque for braking.

Abstract: Disclosed is a fail-safe control method for an automatic transmission having a one-way clutch comprising the steps of determining if shifting into a drive D range is completed; determining if synchronization into a first speed has occurred; and determining if roll-over of a one-way clutch has occurred, and if it has, controlling a friction element of a hydraulic control system so that forced shifting into the first speed is performed.

Abstract: An electronic control system for an automatic transmission has an electronic control unit including a CPU and a memory. The control program is programmed based on an object-oriented programming. An object such as a domain control unit or individual control parts are provided for driving a corresponding linear solenoid valve. A shift request output unit determines types of required shift and outputs a shift request message including the shift type. The domain control unit determines a method to be executed in response to the shift type ID. Preferably, the shift request output unit further determines whether the shift is a single shift or a multiple shift and whether the shift is a normal shift or a special shift. These determination results are also included in the shift request message, so that the domain control unit varies the method to control the linear solenoid valves.

Abstract: A neutral position determination method for a speed change gear shaft of an electrically operated speed change gear can accurately detect a rotational position of a speed change gear shaft without the necessity for a complicated assembling operation. The method includes a speed change gear shaft which is rocked to one side or the other side by a drive motor and an angle sensor for detecting a rotational angle of the speed change gear shaft for executing predetermined speed change control based on a rocking direction and a rocking angle from a neutral position of the speed change gear shaft. Furthermore, rotational angles of the speed change gear shaft when the speed change gear shaft is rocked to a rotational limit on the one side or the other side are detected, and a middle point of a rotational angle detected from the rotational limits of the one side and the other side is updated in registration as a neutral position of the speed change gear shaft.

Abstract: A method for controlling the speed of an off-the-road vehicle traveling on a gradient permits a constant downhill speed to be maintained. The vehicle speed can be set to a constant descending speed by an electronic system through active braking intervention, without requiring actuation of the brake by the driver. The vehicle in which the method is practiced has several forward speeds and one reverse speed within a low-range traveling phase. The constant descending speed is dependent upon the position of the gas pedal and upon the currently engaged gear of the low-range traveling phase. The method for use in off-the-road vehicles is particularly advantageous for situations in which the braking action of the engine on steep gradients is no longer sufficient to decelerate the vehicle.